using System.Diagnostics;
using System.IO;

class Program
{
    static void Main()
    {
        File.WriteAllText("out", "!dlroW olleH");

        var process = new Process();
        process.StartInfo.UseShellExecute = false;
        process.StartInfo.FileName = "rev";
        process.StartInfo.Arguments = "out";

        process.Start();
        process.WaitForExit();
    }
}